thermal: Add Mediatek thermal driver for mt2701.

This patch adds support for mt2701 chip to mtk_thermal,
and integrate both mt8173 and mt2701 on the same driver.
MT8173 has four banks and five sensors, and MT2701 has
only one bank and three sensors.
Signed-off-by: Dawei Chien <dawei.chien@mediatek.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>